Receiver, transmitter, feedback device, transceiver and signal processing method

ABSTRACT

The present invention provides a receiver, a transmitter, a transmitter feedback device, and corresponding methods. The feedback device includes: a multi-channel frequency selection band-pass circuit, configured to receive a multi-frequency band feedback signal, and output a feedback signal of each frequency band in a time-division manner; a feedback local oscillator, configured to provide feedback local oscillation corresponding to each frequency band in a time-division manner; a mixer, configured to mix the feedback signal of each frequency band from the multi-channel frequency selection band-pass circuit and the feedback local oscillation corresponding to each frequency band from the feedback local oscillator, and output an intermediate frequency signal of each frequency band in a time-division manner. A solution in which only one set of signal processing channels is used to process the signals of multiple frequency bands in the uplink, the downlink or both the uplink and downlink is provided.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Application NoPCT/CN2011/070420, filed on Jan. 20, 2011, which claims priority toChinese Patent Application No. 201010000798.1, filed on Jan. 20, 2010,all of which are hereby incorporated by reference in their entireties.

FIELD OF THE INVENTION

The present invention relates the field of communications technologies,and in particular, to a receiver, a transmitter, a transmitter feedbackdevice, a transceiver, a method for transmitting a multi-frequency bandsignal, a method for receiving a multi-frequency band signal, and amethod for processing a transmitter feedback signal.

BACKGROUND OF THE INVENTION

The wireless communication technology has undergone development phasesfrom analog communication to digital communication, from single carrier(Single carrier) communication to multi-carrier (Multi-carrier)communication, from single-mode (Single-Mode) communication tomulti-mode (Multi-Mode) communication. At present, a multi-frequencyband (Multi-Frequency Band) communication technology becomes a next hottopic that manufacturers of communications devices and researchinstitutes focus on.

The frequency band refers to spectrum resources distributed in certainbandwidth, and the multi-frequency band refers to a combination of twoor more frequency bands separated by a certain distance at a spectrum.For example, in a UMTS (Universal Mobile Telecommunications System,universal mobile telecommunications system), a frequency band Band 1 hasa downlink of 2110 MHz to 2170 MHz and an uplink of 1920 MHz to 1980MHz. In the TD-SCDMA (Time Division-Synchronous Code Division MultipleAccess, time division-synchronous code division multiple access), afrequency band A is 1880 MHz to 1900 MHz, and a frequency band B is 2010MHz to 2025 MHz. The multi-frequency band may be a combination offrequency bands for different standards, for example, frequency bandsfor the UMTS and the LTE (Long Term Evolution, long term evolution); andmay also be a combination of different frequency bands for the samestandard, for example, the frequency band A and the frequency band B inthe TD-SCDMA.

A multi-frequency band telecommunications system is also referred to asa multi-standard telecommunications system. In the multi-frequency bandtelecommunications system, a transceiver (Transceiver) may receive andsend radio frequency signals on multiple frequency bands at the sametime. A key apparatus in the multi-frequency band telecommunicationssystem is a multi-frequency band transceiver. At present, an appliedsolution of the multi-frequency band transceiver is referred to as amulti-density transceiver. The multi-density transceiver directly usesmultiple sets of discrete components to constitute multiple radiofrequency channels to process different frequency band signals, or usesa highly integrated semiconductor process to integrate multiple radiofrequency transceiver channels inside one same system in a package(System in a package, SIP) or an IC (Integrated circuit, integratedcircuit). A set of signal processing channels usually includes adownlink channel, an uplink channel and a feedback channel. The downlinkchannel usually includes modules such as a digital part, a digitalanalog converter, a modulator or a mixer, an amplifier, a poweramplifier, and a frequency band filter, and the uplink channel usuallyincludes modules such as a frequency band filter, an LNA (Low NoiseAmplifier, low noise amplifier), an amplifier, a mixer or a demodulator,an analog digital converter, and a digital part.

However, for the practice that multiple radio frequency transceiverchannels are integrated in one same system in a package or an IC byusing the highly integrated semiconductor process, there is a problemwhether an isolation degree and performance of the radio frequencysignal of different frequency bands can satisfy protocol requirements.When multiple sets of discrete components directly constitute multipleradio frequency channels to process different frequency band signals,the problem of the isolation degrees and the performance of differentfrequency bands may be solved, but the problems that the apparatus has ahuge volume, high power consumption, and a high cost occur. Similarly,the multi-frequency band signal brings about higher requirements for thebandwidth supported by the feedback channel, and the problem same asthat in the multi-radio frequency transceiver channel also exists in themulti-channel solution of the feedback channel.

SUMMARY OF THE INVENTION

Embodiments of the present invention provide a transmitter feedbackdevice, a transmitter, a receiver, a transceiver, a method forprocessing a transmitter feedback signal, a method for transmitting amulti-frequency band signal, and a method for receiving amulti-frequency band signal, so as to reduce the volume, powerconsumption and cost of the apparatus for processing a multi-frequencyband signal.

In one aspect, the present invention provides a transmitter feedbackdevice, which includes:

a multi-channel frequency selection band-pass circuit, configured toreceive a multi-frequency band feedback signal coupled at a downlinkline between a transmitter downlink radio frequency channel and anantenna, and output a feedback signal of each frequency band in themulti-frequency band feedback signal in a time-division manner, wherethe multi-frequency band feedback signal includes feedback signals of atleast two frequency bands; a feedback local oscillator, configured toprovide a feedback local oscillation corresponding to each frequencyband in a time-division manner; a mixer, configured to mix the feedbacksignal of each frequency band from the multi-channel frequency selectionband-pass circuit and the feedback local oscillation corresponding toeach frequency band from the feedback local oscillator, and output anintermediate frequency signal of each frequency band in a time-divisionmanner; and an analog digital converter, configured to perform analogdigital conversion on the intermediate frequency signal of eachfrequency band to obtain a digital signal of each frequency band.

In another aspect, the present invention provides a transmitterincluding the feedback device.

In another aspect, the present invention provides a transmitter, whichincludes: a digital frequency shifter, configured to perform, onbaseband I digital signals and baseband Q digital signals of multiplefrequency bands, digital frequency shift to a frequency corresponding toeach frequency band, respectively, where the multiple frequency bandsinclude at least two frequency bands; a combiner, configured to combinethe I digital signals and the Q digital signals of multiple frequencybands, which are after digital modulation, into a multi-frequency bandcombined I digital signal and a multi-frequency band combined Q digitalsignal, respectively; a first digital analog converter and a seconddigital analog converter, configured to convert the multi-frequency bandcombined I digital signal and the multi-frequency band combined Qdigital signal into a multi-frequency band combined I analog signal anda multi-frequency band combined Q analog signal, respectively; a firstreconstruction filter and a second reconstruction filter, configured tofilter the multi-frequency band combined I analog signal and themulti-frequency band combined Q analog signal, respectively; a downlinklocal oscillator, configured to provide local oscillation; a quadraturemodulator, configured to modulate the multi-frequency band combined Ianalog signal and the multi-frequency band combined Q analog signal intoa radio frequency signal of multi-frequency bands by using the localoscillation provided by the downlink local oscillator; and an amplifier,configured to amplify the radio frequency signal of multi-frequencybands.

In another aspect, the present invention provides a receiver, whichincludes: an amplification device, configured to amplify a receivedradio frequency signal of multi-frequency bands, where themulti-frequency bands include at least two frequency bands; an uplinklocal oscillator, configured to provide local oscillation; a quadraturedemodulator, configured to turn the local oscillation provided by theuplink local oscillation oscillator into two quadrature carriers, mixthe radio frequency signal of multi-frequency bands and two quadraturecarriers received from the amplification device, respectively, andoutput a multi-frequency band I analog signal and a multi-frequency bandQ analog signal; a first anti-aliasing filter and second anti-aliasingfilter, configured to perform anti-aliasing filtering on themulti-frequency band I analog signal and the multi-frequency band Qanalog signal, respectively; a first analog digital converter and asecond analog digital converter, configured to convert themulti-frequency band I analog signal and the multi-frequency band Qanalog signal, which are after anti-aliasing filtering, into amulti-frequency band I digital signal and a multi-frequency band Qdigital signal, respectively; a channel separation device, configured toseparate an I digital signal and a Q digital signal corresponding toeach frequency band from the multi-frequency band I digital signal andthe multi-frequency band Q digital signal, respectively; and a digitalfrequency shifter, configured to perform, on the I digital signal andthe Q digital signal of each frequency band, digital frequency shiftinto baseband signals.

In another aspect, the present invention provides a transceiverincluding the transmitter, the receiver and the feedback device.

In another aspect, the present provides a method for processing atransmitter feedback signal, which includes: outputting, in atime-division manner, a feedback signal of each frequency band in amulti-frequency band feedback signal coupled at a downlink line betweena transmitter downlink radio frequency channel and an antenna, whereeach frequency band includes at least two frequency bands; generating afeedback local oscillation corresponding to each frequency band in atime-division manner; mixing the feedback signal of each frequency bandoutput in a time-division manner and the feedback local oscillationcorresponding to each frequency band, and outputting an intermediatefrequency signal of each frequency band; and performing analog digitalconversion on the intermediate frequency signal of each frequency bandto generate a digital signal of each frequency band.

In another aspect, the present provides a method for transmitting amulti-frequency band signal, which includes: performing, on baseband Idigital signals and baseband Q digital signals of multiple frequencybands, digital frequency shift to a frequency corresponding to eachfrequency band, respectively, where the multiple frequency bands includeat least two frequency bands; combining a I digital signals and Qdigital signals of multiple frequency bands respectively to obtain amulti-frequency band combined I digital signal and a multi-frequencyband combined Q digital signal; converting the multi-frequency bandcombined I digital signal and the multi-frequency band combined Qdigital signal into a radio frequency analog signal of multi-frequencybands; and transmitting the radio frequency analog signal ofmulti-frequency bands through a multi-frequency band antenna.

In another aspect, the present provides a method for receiving amulti-frequency band signal, which includes: demodulating a receivedradio frequency signal of multi-frequency bands with a quadraturedemodulator to obtain a multi-frequency band I analog signal and amulti-frequency band Q analog signal, where the multi-frequency bandsinclude at least two frequency bands; performing analog digitalconversion on the multi-frequency band I analog signal and themulti-frequency band Q analog signal to obtain a multi-frequency band Idigital signal and a multi-frequency band Q digital signal; performingchannel separation on the multi-frequency band I digital signal and themulti-frequency band Q digital signal to obtain an I digital signal anda Q digital signal of each frequency band; and obtaining a baseband Idigital signal and a baseband Q digital signal of each frequency bandaccording to the I digital signal the Q digital signal of each frequencyband.

With the transmitter, the receiver, the transceiver, the transmitterfeedback device, the signal transmitting method, the signal receivingmethod, the feedback signal processing method of the present invention,a set of downlink radio frequency channels, uplink radio frequencychannels or feedback radio frequency channels may be adopted to receivea multi-frequency band signal, transmit a multi-frequency band signal orprocess a feedback multi-frequency band signal, so as to reduce a volumeand the power consumption of the apparatus for processing amulti-frequency band signal, and decrease the cost.

BRIEF DESCRIPTION OF THE DRAWINGS

To illustrate the technical solutions according to the embodiments ofthe present invention or in the prior art more clearly, the accompanyingdrawings needed for describing the embodiments or the prior art areintroduced below briefly. Apparently, the accompanying drawings in thefollowing descriptions merely show some of the embodiments of thepresent invention, and persons skilled in the art may obtain otherdrawings according to the accompanying drawings without creativeefforts.

FIG. 1 is a block diagram of a multi-frequency band transceiveraccording to an embodiment of the present invention;

FIG. 2 is a block diagram of an uplink radio frequency channel accordingto an embodiment in FIG. 1;

FIG. 3 is a block diagram of a downlink radio frequency channelaccording to an embodiment in FIG. 1;

FIG. 4 is a block diagram of a feedback radio frequency channelaccording to an embodiment in FIG. 1;

FIG. 5 is a block diagram of an uplink signal digital processing part ofa digital processing module according to an embodiment of the presentinvention;

FIG. 6 is a block diagram of a downlink signal digital processing partof a digital processing module according to an embodiment of the presentinvention;

FIG. 7 is a block diagram of a transmitter including a feedback deviceaccording to an embodiment of the present invention;

FIG. 8 is a flow chart of a method for transmitting a multi-frequencyband signal according to an embodiment of the present invention;

FIG. 9 is a flow chart of a method for receiving a multi-frequency bandsignal according to an embodiment of the present invention;

FIG. 10 is a flow chart of another method for receiving amulti-frequency band signal according to an embodiment of the presentinvention;

FIG. 11 is a flow chart of a method for processing a multi-frequencyband feedback signal according to an embodiment of the presentinvention;

FIG. 12 is a flow chart of another method for processing amulti-frequency band feedback signal according to an embodiment of thepresent invention; and

FIG. 13 is a flow chart of performing local oscillation suppressionusing a method for processing a multi-frequency band feedback signalaccording to embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The present invention is described in all rounds with reference to theaccompanying drawings. In the accompanying drawings, a same markrepresents a same or similar component or a same or similar element.

In the embodiments in the following, the following English abbreviationshave the following meaning, DAC refers to a digital analog converter(Digital Analog Converter, DAC), ADC refers to an analog digitalconverter (Analog Digital Converter, ADC), SAW refers to a surfaceacoustic wave (Surface Acoustic Wave), and DPD refers to digitalpre-distortion (Digital Pre-Distortion).

In this embodiment, a multi-frequency band signal refers to a signalincluding two or more frequency bands; a central frequency of multiple(pieces of) frequency bands refers to an intermediate value between ahighest frequency and a lowest frequency in all the frequency bands; andthe central frequency of each frequency band refers to the intermediatevalue between the highest frequency and the lowest frequency of eachfrequency band.

For example, the multi-frequency band signal includes 3 frequency bands:a frequency band 1 (2100, 2120), a frequency band 2 (2000, 2020), and afrequency band 3 (1700, 1720), the central frequency of each frequencyband is: the frequency band 1 (2110), the frequency band2 (2010), andthe frequency band 3 (1710), respectively; and the central frequency ofthe multiple (pieces of) frequency bands is an intermediate valuebetween the highest frequency and the lowest frequency in all thefrequency bands, (1700 +2120)/2 =1910.

In the case of the DPD (Digital Pre-Distortion, digital pre-distortion),it is assumed that the DPD needs 3 orders, and the bandwidth that the 3frequency bands need are respectively: a frequency band 1 (2080, 2140),a frequency band 2 (1980, 2040), and a frequency band 3 (1680, 1740). Atthis time, the central frequency of the multiple frequency bands is theintermediate value between the highest frequency and the lowestfrequency in all the frequency bands, which is equal to(2140+1680)/2=1910.

FIG. 1 is a block diagram of a multi-frequency band transceiveraccording to an embodiment of the present invention. As shown in FIG. 1,the multi-frequency band transceiver may include an antenna 100, aduplex filter (Duplexer) 110, an uplink radio frequency channel (UplinkRF) 120, a downlink radio frequency channel (Downlink RF) 121, afeedback radio frequency channel (Feedback RF) 122, and a digitalprocessing module (Digital Block) 130. The antenna 100 is an antennaunit capable of transceiving a multi-frequency band signal, or acombination of multiple antenna units transceiving different frequencyband signals. The duplex filter 110 may perform transceivingbidirectional passband passing and stopband suppression, which areneeded for satisfying a protocol index, on a supported multiplefrequency band. The uplink radio frequency channel 120 is mainlyconfigured to receive the multi-frequency band uplink signal from theduplex filter 110, and send the received multi-frequency band uplinksignal, which is turned into a digital signal sequence afteramplification, spectrum shifting and sample quantization, to the digitalprocessing module 130. The downlink radio frequency channel 121 ismainly configured to turn the multi-frequency band digital signalprovided by the digital processing module 130 into a multi-frequencyband analog signal, and transmit, through the duplex filter 11, themulti-frequency band analog signal after spectrum shifting andamplification. The function of the feedback radio frequency channel 122is to perform, through a feedback line 154, coupling and poweramplification on at least one of a non-linear distortion signal at adownlink line 152, an IQ amplitude and imbalanced phase of quadraturemodulation in the downlink radio frequency channel 121, and a localoscillation leakage signal, and send the signal to the digitalprocessing module 130, in which the signal is turned into a digitalsignal sequence after spectrum shifting and analog digital conversion.

Functions completed by the digital processing module may include:

performing rate conversion channel processing and pre-distortion ondigital baseband downlink signals of multiple frequency bands to providea high-speed multi-frequency band digital signal for the downlink radiofrequency channel 121;

controlling a switch at a feedback radio frequency channel to performswitching of each frequency band;

obtaining non-linear data of the downlink radio frequency channel fromthe feedback radio frequency channel 122 and performing operation toobtain a pre-distortion table and analog quadrature modulationdistortion calibration information; and

performing, on a high-speed uplink multi-frequency band digital signalobtained by the uplink radio frequency channel 120, channel separation,quadrature error calibration, and digital down-conversion into abaseband digital signal of each frequency band to provide the basebanddigital signal for the baseband.

It should be noted that, a multi-frequency band transceiver in FIG. 1shows the uplink radio frequency channel 120, the downlink radiofrequency channel 121 and the feedback radio frequency channel 122.Persons skilled in the art should understand that, the device providedby the embodiment of the present invention may include one or more ofthe uplink radio frequency channel 120, the downlink radio frequencychannel 121, and the feedback radio frequency channel 122.Correspondingly, the digital processing module 130 includes one or moreof the foregoing functions.

According to an embodiment of the present invention, carrierconfiguration adopts a digital domain positive and negative frequencyconfiguration manner. That is, a local oscillation frequency ofquadrature modulation/demodulation is configured at a central frequencyof the multiple frequency bands. In a digital domain, two frequencybands separated by a longest distance need to be configured at twosides, and other frequency bands are configured in the middle, and thefrequency of a digital control oscillator for digital frequency shift ofeach frequency band is an intermediate frequency of each frequency bandminus an oscillation frequency. The embodiment of the present inventionmay adopt a double side AQM (Analog Quadrature Modulator, analogquadrature modulator) bandwidth system, which increases the bandwidthtwice as much as that of the system adopting a single-side AQM in theprior art.

For example, as a specific example of the foregoing embodiment, for asignal of two frequency bands, the characteristic of a downlink digitalsignal generated by a digital processing module through controlling thefrequency of the digital control oscillator is that the signal of twofrequency bands including two parts, located in a positive area and anegative area of a complex frequency domain, respectively. For example,the central frequency of a frequency band 1 is 50 MHz, and the centralfrequency of a frequency band 2 is −50 MHz. Because the frequency of thedigital control oscillator for digital frequency shift of each frequencyband is the intermediate frequency of each frequency band minus thelocal oscillation frequency, in this way, the local oscillation of thedownlink radio frequency channel is located in the middle of twofrequency bands that are obtained after the two frequency bands aremixed with the local oscillation, respectively. Similarly, the localoscillation of the uplink radio frequency channel is located in themiddle of the two frequency bands that are obtained after the twofrequency bands are mixed with the local oscillation, respectively. Ifthe system is a TDD system, one same oscillator may be shared totransceive the local oscillation. The digital processing module performsquadrature error calibration on an uplink received signal so thatmirrors of the signals of two frequency bands do not interfere with eachother.

FIG. 2 is a block diagram of an uplink radio frequency channel 120 inthe embodiment corresponding to FIG. 1 according to an embodiment. Asshown in FIG. 2, an uplink radio frequency channel amplifies, by usingan amplification device (for example, a low-noise amplifier (LNA) 270and an amplifier (AMP) 271), a radio frequency signal of multi-frequencybands passing through a duplex filter 110 and then sends the amplifiedsignal to a quadrature demodulator (DeMOD) 272. The quadraturedemodulator 272 converts local oscillation provided by a localoscillator (OSC.) 275 into two quadrature carriers of cos and sin, sothat the multi-frequency band signal from the amplifier 271 are mixedwith two quadrature carriers respectively, and then a multi-frequencyband I analog signal and a multi-frequency band Q analog signal areoutput to a first anti-aliasing filter 273 and a second anti-aliasingfilter 274, respectively. The two multi-frequency band I, Q analogsignals are filtered by the first anti-aliasing filter 273 and thesecond anti-aliasing filter 274, respectively, are then sent to ananalog digital converter 276 and an analog digital converter 277respectively so as to be converted into a multi-frequency band I digitalsignal and a multi-frequency band Q digital signal, and are subsequentlysent to the digital processing module 130. In differenttelecommunications systems, the amplification device may be different.For example, the amplification device may be a two-level low-noiseamplifier, or a SAW filter and a controllable attenuator may be addedafter one level, and so on.

It should be understood that, in the embodiment of the presentinvention, “the multi-frequency band signal from the amplifier 271 aremixed with two quadrature carriers respectively, and then themulti-frequency band I analog signal and the multi-frequency band Qanalog signal are output to the first anti-aliasing filter 273 and thesecond anti-aliasing filter 274, respectively” may specifically be, themulti-frequency band signal from the amplifier 271 is mixed with the twoquadrature carriers, respectively, and then the multi-frequency band Ianalog signal is output to the first anti-aliasing filter 273 and themulti-frequency band Q analog signal is output to the secondanti-aliasing filter 274.

FIG. 3 is a block diagram of a downlink radio frequency channel 121 inFIG. 1 according to an embodiment. As shown in FIG. 3, after a DAC 376and a DAC 377 perform digital analog conversion on the multi-frequencyband combined I digital signal and the multi-frequency band combined Qdigital signal, which are sent by the digital processing module 130,respectively, a multi-frequency band combined I analog signal and amulti-frequency band combined Q analog signal are obtained. Themulti-frequency band combined I analog signal and the multi-frequencyband combined Q analog signal are sent to a first reconstruction filter373 and a second reconstruction filter 374 for filtering, respectively,and then are sent to a quadrature modulator (MOD) 372 respectively to bemodulated by the quadrature modulator 372 into a radio frequency signalof multi-frequency bands, which are sent to an amplifier 371 and a poweramplifier 370 for amplification, and are subsequently transmittedthrough the antenna. The quadrature modulator 372 is connected to thelocal oscillator (OSC.) 375, and the local oscillator 375 provides localoscillation for the quadrature modulator 372.

According to an embodiment of the present invention, the bandwidthsupported by each component (including the DAC, the quadraturemodulator, the amplifier, and the power amplifier) in the downlink radiofrequency channel is a sum of the multi-frequency band bandwidthsatisfying the demand and the bandwidth that the digital pre-distortionof multiple frequency bands need, and the bandwidth supported by eachcomponent (including the ADC, the demodulator, and the amplifier) in thedownlink radio frequency channel is the sum of the multi-frequency bandbandwidth satisfying the requirements and the bandwidth that the digitalpre-distortion of multiple frequency bands need.

FIG. 4 is a block diagram of a feedback radio frequency channel 122 inFIG. 1 according to an embodiment. As shown in FIG. 4, in the feedbackradio frequency channel 122, a feedback line 154 couples a part ofsignals from a downlink line 152, where a coupler usually is attenuationof dozens of dBs, and the signal is sent to a multi-channel frequencyselection band-pass circuit 41 through the feedback line 154. Themulti-channel frequency selection band-pass circuit 41 is configured tooutput the received feedback signal of each frequency band in themulti-frequency band feedback signal in a time-division manner. Afeedback local oscillator (OSC.) 475 is configured to provide feedbacklocal oscillation corresponding to each frequency band for a mixer 474in a time-division manner. The feedback signal output by themulti-channel frequency selection band-pass circuit 41 is sent to themixer 474 to be mixed with the feedback local oscillation, and then anintermediate frequency signal of each frequency band is obtained. Theintermediate frequency signal of each frequency band output by the mixer474 in a time-division manner passes through an anti-aliasing filter 476and is then sent to an ADC 477 for sample quantization to a digitalsignal sequence which is then sent to the digital processing module 130.

According to an embodiment of the present invention, the multi-channelfrequency selection band-pass circuit 41 includes a single-polemulti-throw switch (SW) 470, a second single-pole multi-throw switch(SW) 473, a first frequency band filter 471, and a second frequency bandfilter 472. In the embodiment of the multi-channel frequency selectionband-pass circuit formed of the first single-pole multi-throw switch470, the second single-pole multi-throw switch 473, the first frequencyband filter 471, and the second frequency band filter 472, bycontrolling the first single-pole multi-throw switch 470 and the secondsingle-pole multi-throw switch 473 at the same time, the signal is ableto pass through the first frequency band filter 471 or the secondfrequency band filter 472 at a different time slot, or pass through adirect channel 409 so that the signal is capable of passing throughdirectly. The bandwidth of the first frequency band filter 471 and thesecond frequency band filter 472 may be the bandwidth of the frequencyband, which needs to be passed through, multiplied by a pre-distortionorder (for example, 3 or 5) that the DPD needs.

As an example, the multi-channel frequency selection band-pass circuit41 shown in FIG. 4 includes two filters: the first frequency band filter471 and the second frequency band filter 472. Persons skilled in the artshould understand that, in different embodiments, the number of thefilers included in the multi-channel frequency selection band-passcircuit 41 may be the same as the number of supported frequency bands.

The feedback signals of multiple frequency bands bring about a highrequirement for the bandwidth of the ADC in the feedback channel, andthe feedback ADC usually cannot support such a large bandwidth. In thefeedback channel in the present invention, the feedback signal of eachfrequency band in the multi-frequency band feedback signal coupled at atransmitter is output in a time-division manner by using themulti-channel frequency selection band-pass circuit, the feedback localoscillator is controlled to generate the corresponding local oscillationin a time-division manner at the same time, so that the intermediatefrequency signal, which is obtained after a gated frequency band and thefeedback local oscillation are mixed, is in the anti-aliasing filter ofthe feedback ADC, and the feedback ADC collects the feedback signal.Therefore, the problem that the bandwidth of the multi-frequency bandfeedback signal is too large is solved, and compared with an existingsolution that multiple feedback radio frequency channels are adopted toprocess the feedback signal of each frequency band respectively,improved beneficial effects are produced in the aspects such as thevolume, power consumption, and cost of the apparatus.

FIG. 5 is a block diagram of an uplink signal digital processing part ofa digital processing module 130 according to an embodiment of thepresent invention. As shown in FIG. 5, the uplink signal digitalprocessing part includes a first channel separation module 570, a secondchannel separation module 571, a first distortion compensation module572, a second distortion compensation module 573, a first digitalfrequency shifter 574, a second digital frequency shifter 575, a firstrate converter 576, and a second rate converter 577. The first channelseparation module 570 and the second channel separation module 571receive a multi-frequency band I digital signal and a multi-frequencyband Q digital signal respectively, which are obtained after analogdigital conversion, separate a single-frequency band I digital signaland a single-frequency band Q digital signal from the multi-frequencyband I digital signal and the multi-frequency band Q digital signalrespectively. Distortion compensation on the single-frequency band Idigital signal and the single-frequency band Q digital signal isperformed through a first distortion compensation module 572 and asecond distortion compensation module 573 respectively, and the signalsare turned into baseband digital signals through a first digitalfrequency shifter 574, a second digital frequency shifter 575, a firstrate converter 576, and a second rate converter 577, respectively.

According to an embodiment of the present invention, an uplink localoscillation frequency provided by an uplink local oscillator for aquadrature demodulator is a central frequency of supportedmulti-frequency bands, so that an intermediate frequency signal afterpassing through a quadrature demodulator has an upper sideband and alower sideband symmetrical that are relative to a zero frequency.

It should be understood that, in the embodiment of the presentinvention, the distortion compensation module or the rate conversionmodule may not be included.

For the receiver provided by the present invention, a single uplinkradio frequency channel processes a received radio frequency signal ofmulti-frequency bands, and a digital processing module performs channelseparation on a multi-frequency band digital signal and converts thesignal into the baseband digital signal of each frequency band, whichtherefore solves the problem that the cost, volume, and powerconsumption increase significantly as a multi-density telecommunicationssystem supports the multiple frequency bands, and the problem that theisolation degree and performance of radio frequency signals of differentfrequency bands cannot satisfy a protocol demand because multiple radiofrequency transceiver channels are integrated in one same system in apackage or an IC. In addition, a double-sideband AQM solution may beadopted, and compared with a single-sideband AQM solution, supportedbandwidth expands twice as large, and the bandwidth problem of thesingle-uplink radio frequency channel is solved.

FIG. 6 is a block diagram of a downlink signal digital processing partof a digital processing module 130 according to an embodiment of thepresent invention. As shown in FIG. 6, the downlink signal digitalprocessing part includes a first combiner 670, a second combiner 671, afirst pre-distorter 672, a second pre-distorter 673, a first digitalfrequency shifter 674, and a second digital frequency shifter 675. Thefirst digital frequency shifter 674 and the second digital frequencyshifter 675 are configured to modulate a baseband digital signal of asingle-frequency band to a frequency corresponding to each frequencyband through further shift of modulation and spectrum, respectively. Thefirst pre-distorter 672 and the second pre-distorter 673 are configuredto perform pre-distortion processing on a frequency shiftedsingle-frequency band intermediate frequency digital signal. The firstcombiner 670 and the second combiner 671 are configured to combine an Idigital signal in each single-frequency band digital signal and combinea Q digital signal in each single-frequency band digital signal,respectively, so as to generate a multi-frequency band combined Idigital signal and a multi-frequency band combined Q digital signal,which are then sent to a downlink radio frequency channel. The downlinkradio frequency channel converts the multi-frequency band combined Idigital signal and the multi-frequency band combined Q digital signalinto a radio frequency signal of multi-frequency bands for transmission.

It should be understood that, in the embodiment of the presentinvention, the pre-distorter may also not be included.

According to an embodiment of the present invention, a digital frequencyshifter of the transmitter performs, on the signal of each frequencyband, frequency shift to a frequency which is the frequency of thisfrequency band minus the frequency of downlink local oscillation, wherethe frequency of the downlink local oscillation is set as a centralfrequency of multiple frequency bands. In this way, the intermediatefrequency signal after passing a digital frequency shifter has an uppersideband and a lower sideband symmetrical, which are relative to a zerofrequency.

For the transmitter provided in the present invention, a multi-frequencyband analog signal is processed through a single-downlink radiofrequency channel, which therefore solves the problem that the cost,volume, and power consumption increase significantly as a multi-densitytelecommunications system supports multiple frequency bands, and theproblem that the isolation degree and performance of the radio frequencysignals of different frequency bands cannot satisfy a protocol demandbecause multiple radio frequency transceiver channels are integrated inone same system in a package or an IC. In addition, a double-sidebandAQM solution may be adopted, and compared with a single-sideband AQMsolution, the supported bandwidth expands twice as large, and thebandwidth problem of the single-downlink radio frequency channel issolved.

It should be noted that, each component in the digital processing moduleshown in FIG. 5 and FIG. 6 may be implemented through software,hardware, or a combination of software and hardware. As an example, FIG.5 and FIG. 6 only show processing of signals of two frequency bands, andpersons skilled in the art may easily extend the foregoing structure toprocessing of signals including three or more frequency bands accordingto the instruction of the present invention. In FIG. 5 and FIG. 6,corresponding to two frequency bands, each component includes twocorresponding units (for example, the first combiner 670, the secondcombiner 671, the first pre-distorter 672, the second pre-distorter 673,the first digital frequency shifter 674, and the second digitalfrequency shifter 675), and it should be understood by persons skilledin the art that each component may also include only one unit to processthe digital signal of each frequency band in turns.

FIG. 7 is a block diagram of a transmitter including a feedback deviceaccording to an embodiment of the present invention. For a downlinkradio frequency channel 121 and a feedback radio frequency channel 122of the transmitter in FIG. 7, reference may be made to the descriptionof corresponding FIG. 3 and FIG. 4, and for a downlink signal processingpart of a digital processing module 130, reference may be made to thedescription of corresponding FIG. 6, which are no longer described indetail here for simplicity. The digital processing part of the feedbackdevice of the transmitter and the correlation between the digitalprocessing part of the feedback device of the transmitter and thedownlink signal processing module are described in detail in thefollowing. As shown in FIG. 7, the digital processing module 130 furtherincludes a pre-distortion control unit 770. A pre-distortion controlunit 770 receives a digital feedback signal of each frequency bandoutput from an analog digital converter 477, performs DPD operation in atime-division manner on data of each frequency band sampled in atime-division manner, respectively, and obtains the pre-distortioncorrection signal corresponding to each frequency band to compensate forthe gains of an I digital signal and a Q digital signal of acorresponding frequency band. A pre-distortion correction signalcorresponding to each frequency band may be stored in a pre-distortiontable of each frequency band, the pre-distorter 672 and thepre-distorter 673 may perform pre-distortion processing according to thecontent in the pre-distortion table, and outputs the digital signal ofeach frequency band after pre-distortion processing.

According to an embodiment of the present invention, the digitalprocessing module 130 further includes an error acquisition unit 71,configured to receive the digital signal of each frequency band outputby the analog digital converter, and extract an error correction signalaccording to the digital signal of each frequency band to compensate foran I digital signal and a Q digital signal that are output by thetransmitter. It should be understood that, if a digital processingmodule 130 includes a pre-distorter, the error correction signalobtained by the error acquisition unit 71 may further be used forcompensating for the I digital signal and the Q digital signal that areoutput by the pre-distorter of the transmitter. The error correctionsignal may include at least one of the following signals: a phasecorrection signal, used for compensating for phases of the I digitalsignals and the Q digital signals of multiple frequency bands; and afirst and second DC (Direct Current, direct current) offset signal, usedfor correcting DC offsets of the I digital signals and the Q digitalsignals of multiple frequency bands.

According to an embodiment of the present invention, the erroracquisition unit 71 may include an AQM calibration unit 771. The AQMcalibration unit 771 receives digital feedback signals of two frequencybands of an upper sideband and a lower sideband of downlink localoscillation, where the digital feedback signals are output by an analogdigital converter 477, collect statistics on the correlation on datafeedback signals of the upper sideband and data feedback signals of thelower sideband that are collected in a time-division manner, so that thecorrelation is made 0 to obtain a phase correction signal. The obtainedphase correction signal is acted on I, Q combined signals output by acombiner 670 and a combiner 671, and the AQM calibration is completed.

According to an embodiment of the present invention, the erroracquisition unit 71 may further include a local oscillation suppressionunit 772. The multi-channel frequency selection band-pass circuit 41further includes a direct channel 409, and controls the feedback signalby a switch 470 and a switch 473, so that the feedback signal passesthrough the direct channel 409. The direct feedback signal passesthrough the mixer and is mixed to the frequency of fs/4 (fs is asampling frequency of a feedback ADC) of a feedback ADC 477, and isconverted into a direct digital signal through the analog digitalconverter 477. A local oscillation suppression unit 772 receives adirect data signal output from a feedback analog digital converter (ADC)477, performs quadrature demodulation in a digital domain to obtainleakage information of the downlink local oscillation, that is, a firstDC offset signal and a second DC offset signal, and adjusts a DC offsetof the downlink data so that the local oscillation is suppressed.

Persons skilled in the art should understand that, the error acquisitionunit 71 may include at least one of an AQM calibration unit 771 and alocal oscillation suppression unit 772.

Persons skilled in the art should understand that, the pre-distortioncontrol unit of the present invention may obtain a pre-distortion tableof each frequency band by using multiple pre-distortion processingalgorithms in the prior art, which is not described here again forsimplicity and is not limited. The AQM calibration unit and the localoscillation suppression unit may also implement the function thereof byusing a relevant algorithm in the prior art.

According to an embodiment of the present invention, the feedback devicemay further be a synchronous control module, configured to synchronizeoperations of the multi-channel frequency selection band-pass circuitand the feedback local oscillator, so that the feedback local oscillatorgenerates, at the same time slot, the feedback local oscillationcorresponding to the frequency band of the feedback signal output by themulti-channel frequency selection band-pass circuit at the time slot.

Persons skilled in the art should understand that, the transceiveraccording to the embodiment of the present invention may include thetransmitter feedback device provided by the present invention, and/orthe transmitter provided by the present invention, and/or the receiverprovided by the present invention.

FIG. 8 is a flow chart of a method for transmitting a multi-frequencyband signal of an embodiment of the present invention. Perform, onbaseband I, Q digital signals of multiple frequency bands, digitalfrequency shift to a frequency corresponding to each frequency band,respectively

As shown in FIG. 8, in step 802, channel processing such as rateconversion is performed on baseband I digital signals and baseband Qdigital signals of multiple frequency bands, respectively, and thendigital frequency shift is performed on the signals to a frequencycorresponding to each frequency band, respectively. The frequency ofeach frequency band may be modulated to a frequency, which is thefrequency of the corresponding frequency band minus a downlink localoscillation frequency, respectively. The downlink local oscillationfrequency may be configured as a central frequency of multiple frequencybands. A signal of two frequency bands may be configured in a mirroredmanner in a digital domain by using a zero frequency as a center. Forexample, the sampling rates of baseband I, Q digital signals (AI,AQ),(BI,BQ), and (CI,CQ), . . . , of multiple frequency bands A, B, and C, .. . , may be improved to obtain digital signals (A1I,A1Q), (B1I,B1Q),and (C1I,C1Q), . . . , (A1I,A1Q), (B1I,B1Q), and (C1I,C1Q), . . . , aremodulated to the frequency corresponding to each frequency band (eachfrequency band minus the local oscillation) respectively to obtain(A2I,A2Q), (B21,B2Q), and (C2I,C2Q), . . . ,.

In step 804, the I, Q digital signals of each frequency band arecombined respectively to obtain a multi-frequency band combined Idigital signal and a multi-frequency band combined Q digital signal;where the multi-frequency band combined I, Q digital signals may bemulti-frequency band intermediate frequency combined I, Q digitalsignals. For example, all I paths of (A2I,A2Q), (B2I,B2Q), and(C2I,C2Q), . . . , are combined, and all Q paths of (A2I,A2Q),(B2I,B2Q), and (C2I,C2Q), . . . , are combined, so that amulti-frequency band combined I digital signal Iout and amulti-frequency band combined Q digital signal Qout are obtained. Itshould be understood that, specifically, I digital signals of eachfrequency band may be combined to obtain the multi-frequency bandcombined I digital signal, and Q digital signals of each frequency bandmay be combined to obtain the multi-frequency band combined Q digitalsignal.

In step 806, for example, multi-frequency band combined I, Q digitalsignals are converted into a radio frequency analog signal ofmulti-frequency bands, i.e. a multi-frequency band radio frequencyanalog signal, through a single-downlink radio frequency channel In adownlink radio frequency channel, the downlink local oscillation isgenerated by using the downlink local oscillator, and the modulatormodulates the multi-frequency band combined I, Q digital signals to aradio frequency analog signal of multi-frequency bands including thefrequency bands.

In step 808, the radio frequency analog signal of multi-frequency bandsis transmitted through a multi-frequency band antenna. Themulti-frequency band antenna may be an antenna unit transmitting asignal of multiple frequency bands, or a combination of multiple antennaunits that transceive signals of different frequency bands,respectively.

FIG. 9 is a flow chart of a method for receiving a multi-frequency bandsignal according to an embodiment of the present invention.

As shown in FIG. 9, in step 902, a quadrature demodulator demodulates areceived radio frequency signal of multi-frequency bands to obtainmulti-frequency band I, Q analog signals.

In step 904, analog digital conversion is performed on themulti-frequency band I, Q analog signals to obtain multi-frequency bandI, Q digital signals.

In step 906, channel separation is performed on the multi-frequency bandI, Q digital signals to obtain I, Q digital signals of each frequencyband.

In step 908, baseband I, Q signals of each frequency band are obtainedaccording to baseband I, Q digital signals of each frequency band. Thedigital frequency shift is performed on the separated I,Q digitalsignals of each frequency band to the baseband, and the processing of,such as reducing a sampling rate after frequency selection by a digitalfilter is performed, so that baseband I,Q digital signals of eachfrequency band are obtained.

FIG. 10 is a flow chart of another method for receiving amulti-frequency band signal according to an embodiment of the presentinvention.

As shown in FIG. 10, in step 1002, local oscillation 275 is configuredwith a digital processing module 130, so that two frequency bands A, Bare mirrors of each other about an uplink local oscillation frequency.

In step 1004, after a quadrature demodulator 272 demodulates the radiofrequency signal including the A frequency band and the B frequencyband, multi-frequency band analog signals (AI+BI, AQ+BQ) are obtained,where both AI and BI are output in an I path, and both AQ and BQ areoutput in a Q path.

In step 1006, the multi-frequency band analog signal AI+BI passesthrough a first anti-aliasing filter 273 and a first analog digitalconverter 276 and then a multi-frequency band I digital signalAdigI+BdigI is obtained; a multi-frequency band analog signal AQ+BQpasses through a second anti-aliasing filter 274 and a second analogdigital converter 277, and then a multi-frequency band Q digital signalAdigQ+BdigQ is obtained.

In step 1008, channel separation is performed on multi-frequency bandI,Q digital signals (AdigI+BdigI, AdigQ+BdigQ) respectively to obtain(AdigI, AdigQ) and (BdigI, BdigQ).

In step 1010, after quadrature error compensation and direct currentremoval are performed by using (AdigI, AdigQ) and (BdigI, BdigQ),digital frequency shift is performed to obtain respectivedouble-frequency band baseband I, Q signals.

FIG. 11 is a flow chart of a method for processing a multi-frequencyband feedback signal according to an embodiment of the presentinvention.

As shown in FIG. 11, in step 1102, a feedback signal of each frequencyband in a multi-frequency band feedback signal coupled at a transmitteris output through a multi-channel frequency selection band-pass circuitin a time-division manner.

In step 1104, a feedback local oscillator generates local oscillationcorresponding to each frequency band in a time-division manner.

In step 1106, the feedback signal of each frequency band output in atime-division manner is mixed with the local oscillation correspondingto each frequency band, and the intermediate frequency signal of eachfrequency band is output.

In step 1108, analog to digital conversion is performed on theintermediate frequency signal of each frequency band, and the digitalsignal of each frequency band is generated.

FIG. 12 is a flow chart of another method for processing amulti-frequency band feedback signal according to an embodiment of thepresent invention. The procedure is described with reference to FIG. 7.

As shown in FIG. 12, in step 1202, multiple frequency bands Arf, Brf,and Crf, . . . , output from a power amplifier are directly coupled intosignals, the coupling attenuation is about dozens of dBs, and coupledsignals Arfc, Brfc, and Crfc, . . . , are obtained.

In step 1204, single-pole multi-throw switches 470 and 473 arecontrolled, so that a coupled signal Arfc of Arf frequency band passesthrough a frequency band filter.

In step 1206, local oscillation 475 is controlled, so that Arfc passesthrough a mixer 474 and is mixed to an intermediate frequency to obtainAifc.

In step 1208, sample the Aifc through a feedback ADC 477 to obtain adigital signal Adigc.

In step 1210, the digital processing module 130 performs pre-distortioncomputation on Adigc to obtain a pre-distortion table which acts ondigital signals (A2I, A2Q) after digital frequency shift by using apre-distorter, and the A frequency band pre-distortion processing iscompleted.

Similarly, the process turns to step 1204, the switches 470 and 473 arecontrolled to perform the same closed-loop processing on a frequencyband Brf until step 1210 is completed, and pre-distortion processing onB frequency band is completed; and similarly, the pre-distortionprocessing on a frequency band Crf is implemented. It should beunderstood that, the sequence of performing pre-distortion processing oneach frequency band may be changed, and the present invention does notlimit a specific sequence of the pre-distortion processing.

An embodiment of a method for processing a multi-frequency band feedbacksignal of the present invention may further include: collecting feedbacksignals of two frequency bands (for example, a frequency band D and afrequency band E) located in an upper sideband and a lower sideband ofdownlink local oscillation to obtain Ddigc and Edigc. The digitalprocessing module collects statistics on the correlation on Ddigc andEdigc to obtain a phase calibration signal to act on a multi-frequencyband combined I digital signal Iout and a multi-frequency band combinedQ digital signal Qout.

FIG. 13 is a flow chart of performing local oscillation suppressionthrough a method for processing a multi-frequency band feedback signalaccording to an embodiment of the present invention.

As shown in FIG. 13, in step 1302, multiple frequency bands Arf, Brf,and Crf, . . . , output from a power amplifier are directly coupled intosignals, the coupling attenuation is about dozens of dBs, and coupledsignals Arfc, Brfc, and Crfc, . . . , are obtained.

In step 1304, switches 470 and 473 are controlled so that the signaldirectly passes through a direct channel 409 instead of a filter.

In step 1306, local oscillation 475 is controlled, so that downlinklocal oscillation and feedback local oscillation are mixed to a feedbackintermediate frequency to obtain LOtxif (a feedback intermediatefrequency signal).

In step 1308, a feedback ADC 477 samples LOtxif.

In step 1310, after sampling, sample of LOtxif is sent to a digitalprocessing module 130 for quadrature error and direct current errorestimation to obtain a DC offset calibration signal, which acts on amulti-frequency band combined I digital signal Iout and amulti-frequency band combined Q digital signal Qout; and the oscillationsuppression is completed.

It should be noted that, the embodiment of the present invention notonly may be applied to a base station, but also may be applied to aterminal apparatus. In a telecommunications system according to theembodiment of the present invention, different address access methodsmay be adopted. The system may use the LTE, the CDMA (Code DivisionMultiple Access, code division multiple access), the WCDMA (Wide CDMA,wideband code division multiple access) or the TDMA (Time DivisionMultiple Access, time division multiple access). The embodiments of thepresent invention are not limited to the transmitter, the receiver, thetransceiver, or the feedback radio frequency channel of the transmitterin a telecommunications system. The embodiments of the present inventionmay be applied to any transmitter, receiver, transceiver, or feedbackradio frequency channel of the transmitter.

The sequence numbers in the embodiments of the present invention merelyintend to make the description clearer, and do not imply the preferenceamong the embodiments.

Only one set of uplink, downlink and feedback radio frequency channelsis used in the method for transmitting a multi-frequency band signal,the method for receiving a multi-frequency band signal, and the methodfor processing a feedback signal, which are provided by the presentinvention, to support multiple frequency bands to work synchronously orasynchronously, and the problem that the cost, volume, and powerconsumption increase significantly because the multi-densitytelecommunications system supports the multiple frequency bands to workat the same time is solved.

The embodiments of the present invention are provided forexemplification and description, but are not exhaustive or intended tolimit the present invention to the disclosed form. The sequence numbersof the embodiments of the present invention are merely intend to makethe description clearer, and do not imply the preference among theembodiments. The embodiments are selected and described for illustratingthe principle and actual application of the present invention in abetter way, and enabling persons skilled in the art to understand theinvention and design various embodiments for specific purposes withvarious modifications.

What is claimed is:
 1. A transmitter feedback device, comprising: amulti-channel frequency selection band-pass circuit, configured toreceive a multi-frequency band feedback signal including feedbacksignals of at least two frequency bands coupled at a downlink linebetween a transmitter downlink radio frequency channel and an antenna,and output a feedback signal of each of the at least two frequency bandsin the multi-frequency band feedback signal in a time-division manner; afeedback local oscillator, configured to generate a feedback localoscillation corresponding to each of the at least two frequency bands ina time-division manner; a mixer, configured to mix the feedback signalof each of the at least two frequency bands from the multi-channelfrequency selection band-pass circuit and the feedback local oscillationcorresponding to each of the at least two frequency bands from thefeedback local oscillator to output an intermediate frequency signal ofeach of the at least two frequency bands in a time-division manner; andan analog to digital converter, configured to perform an analog todigital conversion on the intermediate frequency signal of each of theat least two frequency bands to obtain a digital signal of each of theat least two frequency bands.
 2. The transmitter feedback deviceaccording to claim 1, further comprising: a pre-distortion controlmodule, configured to receive the digital signal of each of the at leasttwo frequency bands output in a time-division manner, and obtain apre-distortion correction signal of each of the at least two frequencybands through pre-distortion computation to compensate for gains of an Idigital signal and a Q digital signal of each of the at least twofrequency bands.
 3. The transmitter feedback device according to claim1, further comprising: an error acquisition unit, configured to receivethe digital signal of each of the at least two frequency bands output bythe analog to digital converter, and extract an error correction signalaccording to the digital signal of each of the at least two frequencybands to compensate for an I digital signal and an Q digital signal ofeach of the at least two frequency bands.
 4. The transmitter feedbackdevice according to claim 3, wherein, the error correction signalcomprises: a phase correction signal, used for compensating for phasesof a multi-frequency band combined I digital signal and Q digitalsignal; wherein the error acquisition unit comprises: an analogquadrature modulator (AQM) calibration module, configured to receivedigital signals located in two frequency bands, an upper sideband and alower sideband of downlink local oscillation in each of the at least twofrequency bands, and collect statistics on the correlation according tothe digital signals of the two frequency bands to obtain the phasecorrection signal; and/or the multi-channel frequency selectionband-pass circuit further comprises a direct channel, wherein the errorcorrection signal comprises: a first direct current (DC) offset signaland a second DC offset signal, used for correcting DC offsets of themulti-frequency band combined I digital signal and Q digital signal,respectively; wherein the error acquisition unit comprises: a localoscillation suppression module, configured to receive a direct digitalsignal output after passing through a direct channel included in themulti-channel frequency selection band-pass circuit for no frequencyselection and conversion by the analog to digital converter, performquadrature demodulation in a digital domain on the direct digital signalto obtain the first DC offset signal and the second DC offset signal. 5.The transmitter feedback device according to claim 1, wherein themulti-channel frequency selection band-pass circuit comprises a firstsingle-pole multi-throw switch, a second single-pole multi-throw switchand at least two frequency band filters connected between the firstsingle-pole multi-throw switch and the second single-pole multi-throwswitch; the first single-pole multi-throw switch and the secondsingle-pole multi-throw switch are controlled so that themulti-frequency band feedback signal passes through a correspondingfrequency band filter at different periods respectively.
 6. Thetransmitter feedback device according to claim 5, wherein bandwidth ofthe frequency band filter is bandwidth of the feedback signal of onefrequency band passing the frequency band filter which is obtained bymultiplying a pre-distortion order that digital pre-distortion (DPD)needs.
 7. The transmitter feedback device according to claim 1, furthercomprising: a synchronous control module, configured to synchronizeoperations of the multi-channel frequency selection band-pass circuitand the feedback local oscillator, so that the feedback local oscillatorgenerates feedback local oscillation corresponding to the frequency bandof the feedback signal output by the multi-channel frequency selectionband-pass circuit.
 8. A transmitter, comprising a feedback device,wherein the feedback device comprises: a multi-channel frequencyselection band-pass circuit, configured to receive a multi-frequencyband feedback signal including feedback signals of at least twofrequency bands coupled at a downlink line between a transmitterdownlink radio frequency channel and an antenna, and output a feedbacksignal of each of the at least two frequency bands in themulti-frequency band feedback signal in a time-division manner; afeedback local oscillator, configured to generate a feedback localoscillation corresponding to each of the at least two frequency bands ina time-division manner; a mixer, configured to mix the feedback signalof each of the at least two frequency bands from the multi-channelfrequency selection band-pass circuit and the feedback local oscillationcorresponding to each of the at least two frequency bands from thefeedback local oscillator, and output an intermediate frequency signalof each of the at least two frequency bands in a time-division manner;and an analog to digital converter, configured to perform analog todigital conversion on the intermediate frequency signal of each of theat least two frequency bands to obtain a digital signal of each of theat least two frequency bands.
 9. The transmitter according to claim 8,further comprising: a digital frequency shifter, configured to perform,on baseband I digital signals and baseband Q digital signals of the atleast two frequency bands, digital frequency shift to a frequencycorresponding to each of the at least two frequency bands; wherein themultiple frequency bands comprise at least two frequency bands; acombiner, configured to combine the I digital signals of the at leasttwo frequency bands, which are after digital frequency shift, into amulti-frequency band combined I digital signal, and combine the Qdigital signals of the at least two frequency bands, which are afterdigital frequency shift, into a multi-frequency band combined Q digitalsignal; a first digital analog converter, configured to convert themulti-frequency band combined I digital signal into a multi-frequencyband combined I analog signal; a second digital analog converter,configured to convert the multi-frequency band combined Q digital signalinto a multi-frequency band combined Q analog signal; a firstreconstruction filter, configured to filter the multi-frequency bandcombined I analog signal; a second reconstruction filter, configured tofilter the multi-frequency band combined Q analog signal; a downlinklocal oscillator, configured to provide a local oscillation; aquadrature modulator, configured to modulate the multi-frequency bandcombined I analog signal and the multi-frequency band combined Q analogsignal into a radio frequency signal of the at least two frequency bandsby using the local oscillation provided by the downlink localoscillator; and an amplifier, configured to amplify the radio frequencysignal of the at least two frequency bands; wherein the multi-frequencyband feedback signal coupled at the downlink line between thetransmitter downlink radio frequency channel and the antenna is part ofthe amplified radio frequency signal.
 10. The transmitter according toclaim 9, wherein a frequency of the local oscillation of the digitalfrequency shifter is a central frequency of the at least two frequencybands; wherein the central frequency of the at least two frequency bandsis an intermediate value of the highest frequency and the lowestfrequency in all the at least two frequency bands wherein each of the atleast two frequency bands is obtained by multiplying a pre-distortionorder that digital pre-distortion (DPD) needs.
 11. The transmitteraccording to claim 9, further comprising: an error acquisition unit,configured to receive the digital signal of each of the at least twofrequency bands output by the analog to digital converter, and extractan error correction signal according to the digital signal of eachfrequency band to compensate for the baseband I digital signal and thebaseband Q digital signal of each of the at least two frequency bands.12. The transmitter according to claim 11, wherein, the error correctionsignal comprises: a phase correction signal, used for compensating forphases of the multi-frequency band combined I digital signal and Qdigital signal; wherein the error acquisition unit comprises: an analogquadrature modulator AQM calibration module, configured to receivedigital signals located in two frequency bands, an upper sideband and alower sideband of downlink local oscillation in each of the at least twofrequency bands, and collect statistics on the correlation according tothe digital signals of the two frequency bands to obtain the phasecorrection signal; and/or the multi-channel frequency selectionband-pass circuit further comprises a direct channel, wherein the errorcorrection signal comprises: a first direct current DC offset signal anda second direct current DC offset signal, used for correcting DC offsetsof the multi-frequency band combined I digital signal and Q digitalsignal, respectively; wherein the error acquisition unit comprises: alocal oscillation suppression module, configured to receive a directdigital signal output after passing through the direct channel andconversion by the analog to digital converter, perform quadraturedemodulation in a digital domain, and obtain the first DC offset signaland the second DC offset signal.
 13. The transmitter according to claim12, wherein bandwidth of the frequency band filter is bandwidth of thefeedback signal of one frequency band passing the frequency band filterwhich is obtained by multiplying a pre-distortion order that digitalpre-distortion (DPD) needs.
 14. The transmitter according to claim 8,wherein the multi-channel frequency selection band-pass circuitcomprises a first single-pole multi-throw switch, a second single-polemulti-throw switch and at least two frequency band filters connectedbetween the first single-pole multi-throw switch and the secondsingle-pole multi-throw switch; the first single-pole multi-throw switchand the second single-pole multi-throw switch are controlled so that themulti-frequency band feedback signal passes through a correspondingfrequency band filter at different periods respectively.
 15. Thetransmitter according to claim 8, further comprising: a synchronouscontrol module, configured to synchronize operations of themulti-channel frequency selection band-pass circuit and the feedbacklocal oscillator, so that the feedback local oscillator generatesfeedback local oscillation corresponding to the frequency band of thefeedback signal output by the multi-channel frequency selectionband-pass circuit.
 16. A method for processing a feedback signal,comprising: receiving, a multi-frequency band feedback signal coupled ata downlink line between a transmitter downlink radio frequency channeland an antenna, wherein the multi-frequency band feedback signalcomprises feedback signals of at least two frequency bands; outputting,in a time-division manner, a feedback signal of each of the at least twofrequency bands in a multi-frequency band feedback signal; generating afeedback local oscillation corresponding to each of the at least twofrequency bands in a time-division manner; mixing the feedback signal ofeach of the at least two frequency bands and the feedback localoscillation corresponding to each of the at least two frequency bands tooutput an intermediate frequency signal of each of the at least twofrequency bands in a time-division manner; and performing an analog todigital conversion on the intermediate frequency signal of each of theat least two frequency bands to obtain a digital signal of each of theat least two frequency bands.
 17. The method for processing atransmitter feedback signal according to claim 16, further comprising:according to the digital signal of each of the at least two frequencybands, obtaining a pre-distortion correction signal of each of the atleast two frequency bands through pre-distortion computation tocompensate for gains of an I digital signal and a Q digital signal ofeach of the at least two frequency bands.
 18. The method for processinga transmitter feedback signal according to claim 16, further comprising:extracting an error correction signal according to the digital signal ofeach of the at least two frequency bands to compensate for the I digitalsignal and the Q digital signal of each of the at least two frequencybands.
 19. The method for processing the transmitter feedback signalaccording to claim 18, wherein the error correction signal comprises: aphase correction signal, used for compensating for phases of amulti-frequency band combined I digital signal and Q digital signal; andthe extracting an error correction signal comprises: receiving digitalsignals located in two frequency bands, an upper sideband and a lowersideband of downlink local oscillation in each of the at least twofrequency bands, and collecting statistics on the correlation accordingto the digital signals of the two frequency bands to obtain the phasecorrection signal; and/or a first DC offset signal and a second DCoffset signal, used for correcting a DC offset of the multi-frequencyband combined I digital signal and Q digital signal; and the extractingan error correction signal comprises: receiving a direct digital signalobtained by performing mixing and analog to digital conversion on themulti-frequency band feedback signal as a whole, perform quadraturedemodulation in a digital domain on the received digital signal toobtain the first DC offset signal and the second DC offset signal. 20.The method for processing the transmitter feedback signal according toclaim 16, wherein the outputting, in a time-division manner, a feedbacksignal of each of the at least two frequency bands in a multi-frequencyband feedback signal coupled at a downlink line between a transmitterdownlink radio frequency channel and an antenna comprises: outputting,in a time-division manner, a feedback signal of each of the at least twofrequency bands a multi-frequency band feedback signal by controlling afirst signal-pole multi-throw switch and the second single-polemulti-throw switch included in a multi-channel frequency selectionband-pass circuit to make the multi-frequency band feedback signal passthrough a corresponding frequency band filter at different periodsrespectively, wherein the corresponding frequency band filter is one ofat least two frequency band filters connected between the firstsingle-pole multi-throw switch and the second single-pole multi-throwswitch.